Caitlín or Kaitlin or Caitlyn (pronounced [ˈkatʲlʲiːnʲ] Kate-leen) is a female given name of Irish origin. It is the Irish version of the Old French name Cateline[katlin], which comes from Catherine, which in turn comes from the Ancient Greek Αἰκατερίνη (Aikaterine). Catherine is attributed to St. Catherine of Alexandria.[1] Along with the many other variants of Catherine, it is generally believed to mean "pure" because of its long association with the Greek adjective καθαρός katharos (pure), though the name did not evolve from this word.[2]

Historically, the name was only anglicized as Cathleen or Kathleen. In the 1970s, however, non-Irish speakers began pronouncing the name as /ˈkeɪtlɪn/KAYT-lin, which led to many variations in spelling.[3][4][5]